Method of forming hinges



1 1,620,603 March 1927' 'c A. MUNSON METHOD OF FORMING HINGES Filed April 16. 1926 fi I 3%) ia'nfot Patented Mar. 8, 1927.

CHARLES A. MU'NSON, OF NEW vIBIw'JI'liLIN, CONNECTICUT.

METHOD F FORMING HJZNGES.

Application "filed-April 16, 1926. Serial No. 102,530.

a This invention llGliLliBS to hinges, and has particular reference to hinges for use in .cclaznnection with automobile doors and the h e. The object of the present invention is to provide a hinge [of this sort which may be economically manufactured, which has great strength and durability, and which has a neat, pleasing .and thin appearance.

A further object of the invention is to provide an improved method by means of which the hinge lea-f may be economically manuifactured.

More specifically, the aim of the present invention is to provide an improved hinge from sheet cnetal and which hinge diu-lly meets all reqiurements. The body portion of the leaf ,is preferably made of wrought sheet metal of relatively thick gauge :so that it will have great nigidity, strength and durability, thus insuring it against twisting, wanping or breaking under the weigh-t ot the hinged member, such as an automobile door, to which .is itrequently added .a downward pressure by a person entering or leaving the automobile. The knuckle, or knuckles, of the leaf is formed by rolling one end of the lolank back upon itself, the knuckle being of reduced thickness so that the hinge, in which the leaf is incorporated, is given a relatively thin and neat appearance. In

constructing the hinge leaf, the portion of the blank which is to constitute the knuckle is so shaped and operated upon that there r are no observable cracks or crevices in the walls of the knuckle, and the .pintle receiving (opening oil :the knuckle is true in its round-mess and continuity. -B v anaking the knuckle of reduced thickness. the pintle receiving opening of [the knuckle may be relatively large "as compared to the thickness of the wall of the knuckle in order to prevent strain and possible fracture of the metal constituting the knuckle which might occur were the metal bent about a small radius, while at the same time, the external diameter olf the knuckle is maintained within limits which give a thin appearance. Also, r a substantial bearing surface between the pi-nt-le and the knuckle is obtained.

.Other [objects will lee in part obvious and in part pointed out more in detail hereinafter.

The invention accordingly consists in the features of construct-ion, combination of elements and arrangement of pants which .i'natter set forth. and "the scope of the application of which will be indicated in the appended claims.

In the accompanyingdrawings, wherein I have shown, for [illustrative purposes, one embodiment which the present invention may take;

Figure l is a perspective view of a blank from which my improved hinge leaf unay be termed;

Fig. 2 is a plan view of the blank after the end thereof, which is to constitute the knuckle, has been vreduced in thickness;

Fig. 3 is an edge view of the :blank shown in Fig. 2;

Fig. 4 is a 'view similar "toFig. 2, but showing the side edges of the reduced portion of the blank trimmed;

Fig 5 is an edge view at the blank shown in 4;

Fig. 6 is a plan view showing the reduced portion of the ablank rolled .back upon itself lllO form a knuckle;

Fig. 7 is an edge view of what is shown in Fig. 6;

F'g. 8 is .a view similar to Fig. 6, but showing the ends of the knuckle portion trimmed;

Fig. -9 is .an edge view of what is shown in Fig. '8;

Fig. 10 is an edge view of the completed will be exemplified in the construction here- 1 leaf, the opening through the knuckle ha-ving been reamed to make the same tune and round; and

Fig. 11 is a view showing one -form of hinge in which is incouporated my improved leaf.

In carrying out the method of the present invention, a blank/such :as shown in Fig. 1, is cut or stamped from a sheet of wrought metal of =1'elatively thick gauge. In the present illustrative disclosure, the blank is shown as having a body or attaching portion 10 and a knuckle forming portion or tab 11 at one end of the body portion, but it is to be understood that this disclosure is by way of illustration only and, obviously, the configuration of the leaf blank will depend upon the type of hinge in which the completed leaf is to be em ployed. The knuckle forming portion or tab 11 is reduced in thickness, as at 12, for a substantial portion of its length. preferably by swedging or forging this portion of the blank in a cold condition. As will be seen most clearly from Figs. 2 to 5, the depression, formed in the upper face of the tab by the operation of reducing the thickness of the tab, terminates short of the outer end thereof, leaving a portion 13 of substantially the same thickness as that of the body portion 10. The blank, at the juncture of the attaching portion and knuckle forming portion, gradually tapers down in thickness, as at 14:, there being an inclined surface 15 between the bottom surface of the depression and the upper surface of the body portion. The swedging or forging operation causes the metal to flow or spread.

and thus forms a flash or bulge 18 at each side edge of the tab. and these bulges are trimmed away along the dotted lines of Fig. 2 so as to give the tab the shape shown in Fig. 4. During the swedging or forging operation, or subsequent thereto, as desired, the outer end of the tab may be slightly turned up as indicated in Figs. 3 and 5.

The tab is now rolled back upon itself into generally circular form and, preferably, in this operation. the outer end edge 19 of the tab is engaged with the inclined or tapered surface 15. as shown most clearly in Figs. 7 9 and 10. During the operation of rolling the knuckle, or subsequently thereto, the blank may be bent or upset, as at 20, to bring the knuckle into the plane of the body portion. The next operation may consist in trimming or milling the ends of the knuckle so as to bring the samefrom the rough and uneven condition shown in Figs. 6 and 7 to a flat and smooth condition as shown in Figs. 8 and 9. The opening within the knuckle is now made round and true in all respects by a suitable operation as, for example, by means of reaming. The countersunk apertures 21 in the body portion may be made at any desired time during the process.

It is of distinct advantage, in carrying out my process, to provide, at the outer end i of the tab 11, a portion or rib 13 of greater thickness than the reduced portion 12 of the tab for the reason that, when the tab is rolled upon itself into knuckle form, the metal of the rib will fill in the angle or notch which would otherwise be present within the hole adjacent the seam or joint in the knuckle; and'upon reaming out the hole its internal periphery will be continuous and devoid of all perceptible cracks or angles, and thus there will be bad a very finished joint which in no way mars the appearance of the knuckle. It will be seen from Figs. 9 and 10 that the end edge 19 engages snugly against the inclined surface 15 and that the portion of the blank of normal thickness gradually merges or tapers down, as at let, into the reduced Wall of the knuckle.

It will be seen that, by proceeding in accordance with the present invention, my improved hinge leaves may be economically formed from sheet metal, each of the steps of the process being relatively simple. Since the leaf is made of wrought sheet metal, and the body portion of the leaf is of relatively thick gauge, a hinge in which my leaf is incorporated will be extremely sturdy and durable. The knuckle portion, while having a wall of lesser thickness than the body portion, is nevertheless relatively strong and particularly so as the operation of cold swedging the knuckle forming portion gives exceptionally high physical qualities thereto.

In Fig. 11 is shown, for illustrative purposes, a complete hinge, one of the leaves of which is constructed in accordance with the present invention; the other leaf, designated generally by the letter a, has at one end an upturned wall or flange 25 which forms a socket for the knuckle 11. The ends of this socket are closed by webs or projections 26 constituting knucklesfor the pintle 0.

I claim as my invention:

1. The herein described method of forming hinge leaves which consists in stamping a blank from sheet metal, reducing in thickness a portion of said blank adjacent to, but spaced slightly from, one end thereof, thus providing a narrow portion of normal thickness at the end of said blank, rolling said reduced portion back upon itself, trimming the ends of said knuckle, and reaming the hole of said knuckle.

2. The herein described method of forming hinge leaves which consists in stamping out a blank from wrought sheet metal, re ducing in thickness a portion of the blank adjacent to, but spaced slightly from, one end thereof by swedging said portion in cold condition, trimming the side edges of said reduced portion. rolling the reduced portion back upon itself into cylindrical form to constitute a knuckle, and then making the hole in said knuckle true and round.

3. The herein described method of forming hinge leaves which consists in stamping a blank from sheet metal, reducing in thiclc ness a portion of the blank adjacent to, but spaced slightly from, one end thereof, and thus forming in one face of the blank a depression having at one end an inclined surface merging into the body portion of the blank and at the other end a narrow portion of normal thickness, rolling the portion of reduced thickness back upon itself into cylindrical form and abutting the end edge of the blank against said inclined surface, trimming the ends of the knuckle and inaking the hole in the knuckle round and true.

4. The herein described method of forming hinge leaves Which consists in stamping a blank from sheet metal, forming a depression in one face of the blank adjacent to,

but spaced slightly from, the outer end 10 thereof, slightly bending up the outer end of said blank which is of normal thickness,

knuckle, and then reaming the hole in the 15 muckle.

CHARLES A. MUNSON. 

